Osteoporosis is a disease characterized by reduction in bone mass, resulting in a fragile skeleton. It is clear that bone loss occurs in the disease; however, the quality of bone remodeled after the onset of Hthe disease is unknown. We are using synchrotron infrared microspectroscopy to analyze the chemical composition of bone remodeled before versus after the onset of osteoporosis. In our study, female cynomolgus monkeys were ovariectomized or sham-ovariectomized. After ovariectomization, many monkeys developed osteoporosis. After surgery, the monkeys were administered fluorescent drugs every six months for two years prior to necropsy. These fluorochromes (tetracycline, calcein, and xylenol orange) are taken into newly remodeled bone tissue. Thus, by combining fluorescence microscopy and infrared microspectroscopy, we are able to identify and compare the chemical composition of new versus older bone Hgrowth. We are examining the mineral/matrix ratios, mineral composition, and matrix composition as a function of bone age.